n. - Oneness of origin; esp. (Biol.), development of all beings in the universe from a single cell; -- opposed to polygenesis. Called also monism.
n. - That form of reproduction which requires but one parent, as in reproduction by fission or in the formation of buds, etc., which drop off and form new individuals; asexual reproduction.
n. - The direct development of an embryo, without metamorphosis, into an organism similar to the parent organism; -- opposed to metagenesis.